When Travis d’Arnaud was sent back to the minors in early June, it was time for his father to have a serious talk with his son.

The hardest lessons in life are the most valuable.

“We spoke the very next day, and I told him, ‘This is exactly what you need, kid,’ ” Lance d’Arnaud, who was visiting from his home in Southern California, told The Post on Tuesday night at Citi Field before the Mets beat the Braves 3-2.

“Just a chance to get up on your own and get back to basics. Put the big show aside for a while and get back to what you do well.

“For Travis to realize that it could all be taken away, it really made him dig deep and go down to where he really got his talent, and forget about the crowd and hoopla and just get after it.”

“I didn’t get down on myself,’’ Travis said. “I knew I had work to do.’’

“There’s been a lot of setbacks and he’s had more than most but hopefully this is the last one,’’ Lance said of the trades and injuries that Travis has dealt with. “I think that this has all played into his character and his ability to endure the sport, it’s going to be a long haul still.

“Build up some momentum and then hit ’em hard and he did exactly that, he killed it for two weeks,’’ Lance said of Vegas life. “I have never seen a minor league performance like that. I told him to make as much noise as you can, make it impossible for them to keep you here.’’

In 15 games in Las Vegas, d’Arnaud hit .436 with six home runs and 16 RBIs.

He had been hitting .180 for the Mets.

Travis, 25, grew up those two weeks and since returning to the Mets is batting .270 with nine home runs and 23 RBIs.

His 12 home runs are four more than David Wright, three more than Daniel Murphy and a franchise record for a rookie catcher.

In another difficult season for the Mets, Lucas Duda and d’Arnaud are bright spots, along with Juan Lagares, who ripped a two-run home run Tuesday night. D’Arnaud picked up a double and single and scored two runs. He is hitting .375 over his last four games.

With Noah Syndergaard toiling at Triple-A, the d’Arnaud Experience shows good things can come from time in the minors if a player gets his mind right.

“For me it’s nice seeing results but I’ve learned to trust the process,’’ Travis said. “Just letting the numbers come. Instead of trying to manipulate the bat to get a hit, it’s just squaring the ball up.’’

Let your natural talents flow through preparation and hard work.

Be yourself. Trust yourself.

“The success in Vegas really helped me,’’ Travis said.

“I’m proud of the way he mustered his game and got back to business,’’ Lance added. “It was the perfect checkout that he needed, the perfect little respite.’’

Noted Terry Collins: “When we got this guy in the trade [for R.A. Dickey], everybody said, ‘This guy is really going to hit. Not only that he will hit for power.’ Now Travis has shown everybody that.’’

This was Lance’s first visit back to New York since the season opener. Travis’ sister, Lindsey, is a student at NYU.

“It’s perfect, they can watch out for each other in New York,’’ Lance said.

Travis’ older brother, Chase, 27, is doing well with the Pirates Triple-A team after suffering a concussion and a thumb injury the last two seasons and is expected to be called back up to the majors.

“He’s been playing center field, too, and made a grab that was the ESPN Play of the Week,’’ Lance said.